/* @Print.js
 * DH (http://denghao.me)
 * 2017-7-14
 */
;(function (window, document) {
  var Print = function (dom, options) {
    if (!(this instanceof Print)) return new Print(dom, options)

    this.options = this.extend(
      {
        noPrint: '.no-print',
        onStart: function () {},
        onEnd: function () {},
      },
      options,
    )

    if (typeof dom === 'string') {
      this.dom = document.querySelector(dom)
    } else {
      this.dom = dom
    }

    this.init()
  }
  Print.prototype = {
    init: function () {
      var content = this.getStyle() + this.getHtml()
      this.writeIframe(content)
    },
    extend: function (obj, obj2) {
      for (var k in obj2) {
        obj[k] = obj2[k]
      }
      return obj
    },

    getStyle: function () {
      var str = '',
        styles = document.querySelectorAll('style,link')
      for (var i = 0; i < styles.length; i++) {
        str += styles[i].outerHTML
      }
      str += '<style>' + (this.options.noPrint ? this.options.noPrint : '.no-print') + '{display:none;}</style>'

      return str
    },

    getHtml: function () {
      var inputs = document.querySelectorAll('input')
      var textareas = document.querySelectorAll('textarea')
      var selects = document.querySelectorAll('select')

      for (var k in inputs) {
        if (inputs[k].type == 'checkbox' || inputs[k].type == 'radio') {
          if (inputs[k].checked == true) {
            inputs[k].setAttribute('checked', 'checked')
          } else {
            inputs[k].removeAttribute('checked')
          }
        } else if (inputs[k].type == 'text') {
          inputs[k].setAttribute('value', inputs[k].value)
        }
      }

      for (var k2 in textareas) {
        if (textareas[k2].type == 'textarea') {
          textareas[k2].innerHTML = textareas[k2].value
        }
      }

      for (var k3 in selects) {
        if (selects[k3].type == 'select-one') {
          var child = selects[k3].children
          for (var i in child) {
            if (child[i].tagName == 'OPTION') {
              if (child[i].selected == true) {
                child[i].setAttribute('selected', 'selected')
              } else {
                child[i].removeAttribute('selected')
              }
            }
          }
        }
      }

      return this.dom.outerHTML
    },

    writeIframe: function (content) {
      var w,
        doc,
        iframe = document.createElement('iframe'),
        f = document.body.appendChild(iframe)
      iframe.id = 'myIframe'
      iframe.style = 'position:absolute;width:0;height:0;top:-10px;left:-10px;'

      w = f.contentWindow || f.contentDocument
      doc = f.contentDocument || f.contentWindow.document
      doc.open()
      doc.write(content)
      doc.close()
      this.toPrint(w, function () {
        document.body.removeChild(iframe)
      })
    },

    toPrint: function (w, cb) {
      var _this = this
      w.onload = function () {
        try {
          setTimeout(function () {
            w.focus()
            typeof _this.options.onStart === 'function' && _this.options.onStart()
            if (!w.document.execCommand('print', false, null)) {
              w.print()
            }
            typeof _this.options.onEnd === 'function' && _this.options.onEnd()
            w.close()
            cb && cb()
          })
        } catch (err) {
          console.log('err', err)
        }
      }
    },
  }
  window.Print = Print
})(window, document)
